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Friday, 10 September 2010

I Was Wrong...

Okay, I take back what I said about the new Pentax 35mm ƒ/2.4 yesterday. The thing is, Pentax needs a Limited DA 24mm!—badly. Badly. But I won't dwell on that. (Unless I just did.) The thing is, I was wrong about the new lens. Pentax is doing the right thing.

Exhibit One:

The new lens on the new K-r. This looks giant in the picture (ever notice how relative size just doesn't come through in online illustrations?), but it's going to be quite small and light in reality—the body weighs 21 oz. with batteries and card and the lens weighs just 4.4 oz. That's a total of 720g metric.

About the new K-r: its Mama was a K-x, its Papa was a K-7, and remember that old saying about how every new baby is an attempt to take the best of its parents and create a perfect mix?

Exhibit Two. I doubt all these colors will be available in the U.S. or U.K., but the colors are a clear indication that the lens is meant to be an alternative to a kit zoom on the K-r and K-x. That's the right move.

Exhibit Three: The commenters who said that the price of the lens needs to match the price of the camera. They're right.

As Chris Nelson said in the comments, "I think offering an inexpensive prime lens is a great way to get typical zoom consumers interested in the wonderful world of traditional photography. And, I wouldn't be surprised if this lens performs amazingly well." I wouldn't be surprised either.

So Pentax is encouraging K-x and K-r buyers to experience the pleasures of a matched normal prime that goes with those killer little cameras. That's a move I should approve of. I do.

And a final comment: ƒ/2.4 isn't really slow any more. We need to get out of that mindset, I think. In 1980—recent history for me, since I was alive and an adult then ("history" being anything that happened before you were born)—we didn't even have a truly decent 400-speed color print film. ƒ/2.4 is half a stop slower than ƒ/2, but from what I hear, the K-r will have such good high-ISO performance that shooting at ISO 1600 will come with very little penalty and faster ISOs will be feasible. So we lose a quarter from one hand and gain a dollar in the other; the balance is in our favor. Maybe not relative to the best DSLRs of recent times but certainly relative to the not-so-old film days when many still-current lenses were designed and made. Faster lenses are still nice, but they inevitably come with cost and size penalties that aren't always the right tradeoff.

Mike

ADDENDUM: Several commenters have noted a website that has published the block diagrams of the new lens and the old FA lens and that claims they're identical. Here's the post. The two lenses are certainly related, but they're not identical. Right away you can see that element 6 has a larger diameter relative to element 5 in the new lens, and both elements 2 and 5 have greater thickness in the new lens. Furthermore, the specs say that both lenses have 5 groups, and the reproductions of these drawings are so crude you can't even tell which group has the additional airspace—they both look like diagrams of 6/4 lenses. (I suspect elements 4 and 5 are uncemented.)

It's tempting to do so, but you really can't make predictions about lens performance based on cross section diagrams. (All you'd have to do to prove this to yourself would be to test a few of the great variety of almost-identical lenses of similar types—say, Planar-types or Tessar-types.) Very subtle changes in the diameter and degrees of curvature and spacing can affect performance, and of course many factors such as glass type, coatings, and mechanical considerations (baffling, centering, aperture shape, etc.) don't show up in the drawing. Sometimes you can detect shared characteristics typical of design types, sometimes not so much. I am more comfortable evaluating the actual performance of specific lenses. In any event, I wouldn't read too much into crude JPEGs of drawings that show similar arrangements of elements.

Notice any similarity? One is a nondescript single-coated kit lens from the 1970s that can be bought on Ebay for $15; the other is one of the most famous—and expensive—lenses of its type available today.

Note: Links in this post may be to our affiliates; sales through affiliate links may benefit this site. More...Original contents copyright 2010 by Michael C. Johnston and/or the bylined author. All Rights Reserved.

Featured Comment by Wieland W.: "Regarding your addendum, although I agree with you in general, in this specific case I think you should consider the evidence. Please look at the attached image, in which the lens schemes are superimposed in a way to give the same size of the mount. The only difference is a slightly smaller diameter of the elements, which might be due to the reduced aperture."

Mike replies:I understand that. And the two lenses might be identical; the superimposition shows that I was...well, wrong. (How appropriate!) However, what I'm saying is that what we as photographers are interested in is performance, and similar or even identical cross sections are not always a predictor of identical performance. There are too many other factors that are also important.

I think it's wiser to wait for the actual lens, test or try it, and evaluate its actual results, rather than make assumptions based on the block diagram.

Comments

I don't like your encouraging people to think of f/2.4 as "fast". For a normal prime lens, f/2 is NORMAL. Half a stop slower than normal is not fast! QED. :-)

Yeah, I'm a dinosaur. The 50mm lens I still own I bought in 1982.

In 1982 (or 1970) I was shooting at ISO 1600 a lot already. At f/1.4 a lot of the time (or at f/2 at 90mm). Certainly the ISO 1600 today is much less noisy than what I got pushing TRI-X in 1970, which is all to the good. But it is not SO wonderful that I would happily jump up to 3200 or 64oo (even on my D700, which does excel at that; "3200 is the new 400!").

Also, f/2.4 as the widest aperture still gets you quite a lot of depth of field -- especially on a smaller sensor, 1.5x crop factor or thereabouts. Maybe not enough to keep the whole face in focus -- but enough to make the background less a featureless blur and more a block image. So even if you can get an exposure and noise level that suit you, you're still losing out there.

(It may well be that this is the right speed for this lens; for cost reasons, for the role they want it to play. I'm not so much objecting to their selling an f/2.4 lens as to your calling it "fast".)

I think the only negative thing I see in this is that 35mm seems now to be carved in stone as the normal focal length for APS-C. I would have loved to see 28mm (which is near enough the diagonal of an APS-C sensor) considered normal.

I'm not going to argue that it's more right, because it fits a definition of what a normal focal length is, or that it's in some way better. It just happens to be that I really like my normal lenses on the wide side rather than the tight side. Maybe it's just because my normal prime is a Sigma 30mm (I like this focal length enough to have almost bough a Nikon 28mm f/2.8 AI-S to have as a companion to that Sigma – sanity prevailed) but that's how it is. And the focal lengths receiving some prime love at the moment seem to be 24mm and 35mm.

Right now it's 24 and 35mm (new Nikkors, one new Pentax and they've been L-staples at Canon) which is getting the prime attention (no pun intended), although the 24mm options are hardly affordable. 28mm seems to get little attention.

This is also one of the things I miss in the range of M43 lenses. They have the 17 and 20mm but a 14mm would really round things out.

I vote f2.4 is too slow. Erm...if they could make good (great) f2 or faster standard lenses in the 70s, why not now? I understand what you are saying, but there are qualities of fast lenses that aren't exclusively to do with speed. Since the equivalent crop sensor lens is going to have increased depth of field to its full frame equivalent, if you are interested in shallow depth of field, now you are fighting both the shorter focal length of the equivalent lens, and the slower speed.

Yes, I'm sure you can take a perfectly great picture with any of these cameras. But I'm still not sure why you would want to cripple yourself. Yes, shooting at f 1.4 can create some annoying pictures at times and is probably overused, but it has its uses. And since it was something easily available in the past, and as far as I know, there is no good reason that it's still not a possibility, I'm confused as to why it's such a big deal to have it.

That's sum up the opinion I have on this lens. In the past months, I had a lot of advise requests from newbies for making photography on a budget.

While the K-x was easily the best camera "on a budget", I had a very hard time advising for the system as anything more qualitative than the kit lens was doubling the budget.

On the other side you could get a D90 with a 35mm/1.8 at bargain prices.

This lens is soft at 1.8 and anyway 2.8 is enough for "creative" photography at such focal lengths.

Now you will be able to get a K-x + 35mm pack for about 700$/€ or less. Enough for motivating people to get in. Then they will drool on the FA31ltd (I feel that Zeiss avoid releasing it newish 35/1.4 in K-mount to avoid the comparison)

Regarding your request for a 24, Pentax have the superb 21mm/3.2 ltd, which is exactly equivalent to a 35 in 35...

Sure a weathersealed DFA*24mm/2.8 would be nice however (but I would expect it to retail North of 800$/€, another population really)

Mike, I'm for traditional photography. My favourite lens is a 40mm f2. Not only its a sheer pleasure to use but it's making me think more before I click. I feel really involved in the creation of the image.

I, however feels the traditional photographer will be in the minority, thus low volume means high cost (Zeiss?)

On top of that, the onslaught of marketing hype that zoom lenses is the magic wand is too much for the average consumer to bear.

Oh, don't apologize. Pentax makes nice DSLRs; but their lens lineup really is a head-scratcher. Having so many primes is delightful--but you wonder if they use a dartboard to choose their focal lengths and apertures.

One of Pentax's great lapses was the absence any prime priced under $300. It seems that's the hole the 35/2.4 is designed to fill. If this gets offered as an alternate kit lens, that's actually progress, IMO.

But there's still a glaring lack of any truly fast APS-C normal/wide; in addition to the missing 24mm-ish lens you mention.
Make mine 26mm (40e), thanks.

I can't help but to take a look at the complete current line-up of Pentax lenses and I come up with focal lengths such as 15mm, 40mm, 77mm, 31mm and 43mm prime lenses. Then, there are F1.9, F2.4, F3.2 maximum apertures. You won't find such thing in the current Canikon line up, these won't get pass the Marketing department. Also note the number of prime lenses versus number of zoom lenses in the line up. This again tells you something about Pentax.

To me, lens speed isn't about light gathering ability. High ISO has introduced a user-selectable variable into the fixed aperture/shutter speed equation, and the freedom will grow as sensors' light gathering abilites do.

What does this leave us with? For the first time in photographic history, we can select aperture almost at will, regardless of light and subject motion. This means we are free to explore depth of field.

And then they give us lenses with small apertures. Combine that with APS-C sensors and you can figure out for yourself what this does to DoF shallowness.

To me, the main differentiator between a zoom and a fixed focal length lens is the latter's ability to provide shallow DoF. Sure, there are other differences, but nothing shows in pictures nearly as dramatically.

"there are qualities of fast lenses that aren't exclusively to do with speed. Since the equivalent crop sensor lens is going to have increased depth of field to its full frame equivalent, if you are interested in shallow depth of field, now you are fighting...[snip]"

You're making the same mistake I made yesterday. You're taking this lens out of context. It's an entry-level, low-cost kit lens alternative for entry-level and mid-level cameras. Most people want and need *more* depth of field, not less. For us savants with our selective focus needs, there's the very nice, almost too sharp DA 55mm f/1.4.

"To me, the main differentiator between a zoom and a fixed focal length lens is the latter's ability to provide shallow DoF. Sure, there are other differences, but nothing shows in pictures nearly as dramatically."

The fixation with shallow depth of field is a recent phenomenon, provoked by tiny digicam sensors and their corresponding very short lenses. This would not be the right lens to get if you want that effect. There are other, better lenses for that.

The 24/2.4 on a small camera with an APS-C sized sensor looks like a good idea to me. In fact I wish Nikon would make a similar lens as so far my main lens for my 'small' camera (D90) is the 20/2.8 Nikkor, which is neither small nor fast nor exceptionally good.

Knowing Pentax's efforts on the kit lens front, it wouldn't surprise me if this one out-performs the Nikon or Sony budget 35s. That loss of the 1/2 stop of aperture most probably went into optical quality.

And it's got a proper focusing ring. And it'll start appearing on the used market in a few years - allowing people who are merely curious about primes to impulse-buy a secondhand one for $50. And get even more people into primes!

Your comments about iso/aperture irk me. The trend in modern photography, due to the combination of small sensors and *#&#*(#y zoom lenses, is toward infinite DOF at all times.

I think that looks like hell.

As much as possible I like to shoot at f/2 or f/2.8 while nearly never stopping down to f4. Yeah, stopping WAY down to f/4 just ruins the look of most images. Older images such as the Jack Kerouac shot you posted elsewhere today always seem to have shallow DOF, and we are poorer today for the loss of that look, not blessed by the ability to use f/8 in the dark.

As the owner of anew K-7 and a 40/2.8 ltd pancake lens, my response is mostly meh... to this particular lens. I lurve the idea though. I would definitely be interested if they came out with a similar intro lens in the 70-85 mm range.

Two words: Photography course.
This inexpensive prime, when matched to an inexpensive DSLR (or mirrorless camera?) would make a great package for high schools or colleges needing something to keep on hand for photography classes. Remember when every college art department used to have a cabinet filled with K1000 bodies and 50mm f/2 primes?

The single best lens for general photography that I have ever used is the one on my Leica M6 right now: the Zeiss ZM 35 Biogon-C.

The maximum aperture of this lens is f/2.8. I have no problem isolating a subject in an environmental portrait with this lens when it's used wide open. (And yes, the 35 that I had before this was the 35/1.4 Summilux ASPH, as a matter of fact).

If you really want to blur the background, you really need to do only two things:

(1) Shoot an 85mm lens at f/2.8 or larger. Pretty much any 85 ever made will perform this task adequately, and (since this FL is reatively easy to design and manufacture) at least half of them will do it spectacularly. The old Nikkor 85/2 AIS and the Samyang 85/1.4 both do the job about as well as lenses that cost five or ten times as much.

One thing I really enjoy about this site is how you often say something passionate and polarizing, and then follow up with reflections which temper or thoughtfully amplify the original. (The Leica-year posts being another great example.)

I am curious what you think of the 21mm f/3.2 Limited as a 35mm replacement — it gives a field of view about 4° wider.

I get the feeling that unlike other offerings from the other marques at 35, the different colours and the fact it will probably be offered as a kit gives a great story to any potential buyer at the store.

Could you imagine comparing this to a canon / nikon with a zoom? The salesperson could immediately talk about the speed of the lens, the depth of field, etc. and move the conversation away from the body -- to around the kit. Most people upgrading from compact camera land would probably have the mindset of just buying what's in one box anyway.

An intelligent decision here from Pentax marketing that plays well into the hands of anyone wanting an upgrade -- and to help their sales channels differentiate their product and brand.

"Older images such as the Jack Kerouac shot you posted elsewhere today always seem to have shallow DOF, and we are poorer today for the loss of that look..."

In the context of a discussion about a 35/2.4, this is nonsense.

Ginsberg's main camera was reputedly the one that he bought on Robert Frank's advice: a Leica M with the then-current 35mm f/2.8 Zeiss Biogon, and the DOF and perspective in the image in question are completely consistent with that combination.

That's pretty much exactly the same DOF that I get with the contemporary version of the 35/2.8 Biogon. With a 35/2.4 on a 1.5 crop sensor, the OOF circles of confusion will be enlarged, and look even a bit (1.5X) blurrier.

Pentax' attempt to mainstream the "normal" prime is a nice move - wonder if it will catch on, though?
Regarding "normals" for APS/C, I would recommend taking a look at Sigma. I have an older Sigma 28mm F1.8 Asph. II, which is quite compact and performs well in most respects. Its only serious drawback is a tendency for ghosting - something I have seen with other pre-digital lenses, since they are not back-coated. Its newest incarnation - 28mm F1.8 EX DG ASP Macro - is optimized for digital, and might not have that problem. But of course the EX serie is generally quite large and heavy (but well build)

The two gaps I see in the line-up are at 18mm [27mm] and 28mm [42mm]. IMO there would be too much overlap in, say, a 16mmf2. Besides, that wide and that fast it would be huge. Not Nikon 24mm f1.4 huge, but still...

An 18mm f2 would help keep the size under control (vis a vis a 16mm f2) and would fill the gap better.

And is it just me, or does the entire Pentax DA lineup completely smoke the Nikon DX lineup? Primes AND Zooms!

That looks like a great street shooting camera - a modern digital equivalent for your "Leice for a year" followers. The maximum aperture is fine for that. Set it up to shoot black and white JPGs with a yellow filter, 800 ISO, and off you go.

>>> The single best lens for general photography that I have ever used is the one on my Leica M6 right now: the Zeiss ZM 35 Biogon-C <<<

Totally agree. The ZM C-Biogon 35/2.8 is an awesome lens. So is Zeiss' other C-Biogon, the 21/4.5 (which is a touch slow, but one does not usually need to shoot a 21 mm lens at f/2). The trade-off is that it is quite possibly the best-corrected 21 mm lens on earth.

It is much easier for lens designers to achieve optical brilliance when they don't have to stretch the design to a faster speed, and those two lenses are prime examples.

"The fixation with shallow depth of field is a recent phenomenon, provoked by tiny digicam sensors and their corresponding very short lenses. This would not be the right lens to get if you want that effect. There are other, better lenses for that." - Mike

Yeah...but...it used to be that your stock normal 50mm lens was f2, no? Now after denying us normal primes optimized for digital for most of the digital revolution, now we have to pay extra just to get where we started from. Seriously, I find that annoying.

I wonder if the shallow DOF thing is just a reaction to looking at a lot of 35mm pictures from the past that were shot at shallow DOF not for artistic reasons but because there was not enough light. Still, I'd rather shoot ISO 400 at f2 than ISO 1600 at F4. Using the Canon 5D Mark I, which is supposed to have reasonable low light performance, I've found the high ISO pictures to be lacking. I do value a fast lens that lets me keep the ISO low.

"It is a perfect choice for digital SLR beginners to familiarize themselves with the basics of using interchangeable lenses."

Note the use of "beginners" and "basics." Now it might just be me, but this strikes me as a great way to get the kit zoom folks interested in prime lens photography which is really what Pentax does best. I'm not sure most entry level photographers are ready for f1.4. I'm an entry level person and I have a hard time at f1.4. I don't auto focus, but the depth of field at those types of apertures is so small that you need some skill to come up with a good composition. Trust me I speak from experience (mostly bad) on this. F2.4 is a good "fast" aperture for a beginner.

Just my two cents.

And yes, high ISO's do diminish the need for extremely wide apertures.

I think this is a good move from Pentax and I hope they will make some more primes in the line of this Da 35mm/f2.4.

Is it fast, well not superfast but I think it's good enough and even great when sharp from the start.

The most important thing that everyone seems to forget is its targeted buyers. A 18-55mm kitlens has an aperture of f4.5 at 35mm so this prime is two stops faster and that will make a uge difference when dose K-r users take pictures of their family party's at home or so.

Reading this post and replies, I get the sense that offering entry-level primes is a good idea for a company that makes upscale primes of excellent reputation. That sounds right to me.

The other reason this is good news is all those stories (or were they rumors?) about Hoya being ambivalent or unsure about the Pentax division and its future. In that context, a new product that fills a gap in the lineup and thus makes a whole system more competitive, in a way that plays to Pentax's strengths, is a reassuring development.

Tangential, but Edwin's comment about Pentax's unusual focal lengths and max apertures has me wondering how accurate are the more typical "traditional" advertised focal lengths. And, conversely, how much influence marketing has on what focal lengths and apertures may even be considered by the lens designers.

Thanks for your Insight mike. I am most of all a photography Hobbyist or enthusiast..whatever we are called.. Anyway i feel I was (like others) lured in by the "legend of fast lenses". I thought that once I get my f1.4 I too can have the creamy bokeh that the pro's have! I thought i could set the aperture and take pictures at any distance at any focal length and it should give me "the creamy bokeh"
Of course this is not always so as I believe you have demonstrated? And it turns out I do have better luck with my 90 2.8 with the subject close and the background farther away.
I am not suggesting that all who wanted to see an F1.8 instead of F2.4 for the new DA-l35 are "like me" or "wrong" or anything. But I do find it interesting what effect marketing and expectations of "best practice" has on average consumers and their impressions of the immediate results they can get with their new products
.
I keep thinking back to the manual for my Canon point and shoots where they describe Aperture as a sharp background and a blurry background (usually accompanied by a diagram of a person in front of a tree) Boy was I surprised when my experiments did not yield those results.

Now I feel at least I have learned much more and I rarely shoot completely wide open unless absolutely necessary. And if i want to get good subject separation there are of course many things to consider besides speed.

Like some others have said, I value primes mostly for their wider apertures -- partly for their light-gathering ability, but also for their ability to isolate the subject from the background. When shooting a bride getting ready on the wedding day, I sometimes find it would be useful to have something wider than my 50mm, but faster than the f/2.8 of my 16-50mm.

I want a fast 24mm, like Sigma's 24mm f/1.8. If Pentax won't make us one, I'll end up buying the Sigma. It is a full-frame lens, so I can use it on my film camera (which, admittedly, I rarely use), and if Pentax ever releases a full-frame DSLR, I'll have rather versatile full-frame kit: 24mm f/1.8, 50mm f/1.4, 100mm f/2.8 (each a doubling of the previous focal length).

If we ever do get a full-frame Pentax DSLR, I sure hope Pentax follows the Nikon model and gives us the option of automatically cropping the viewfinder and image when a DA lens is attached.

One must applaud any manufacture who comes out with a good, inexpensive normal prime. They are sorely lacking in today's market. Thank you Pentax!

That said, I must strongly disagree with the notion that f/2.4 is 'fast enough'. The problem lay not with the light gathering (although nice) but rather with Depth of Field (specifically the lack of it.) If the market continues to buy lots and lots of slow zooms, the possibility of fast primes gets more and more elusive.

The new lens is yet to be tested in the field. As far as the 40mm F2.8 is concerned that is one special piece of equipment: I use it often wide-open on full-frame film camera such as Pentax ZX-L and I love it at F2.8. And yes, some of that film is Tri-x.

I also use the legendary FA 31m F2.8 on both digital and film and I absolutely love it.

"I think offering an inexpensive prime lens is a great way to get typical zoom consumers interested in the wonderful world of traditional photography."

I'm not convinced that many tyro photographers will appreciate the discipline/learning aspect of choosing the prime when a similarly priced zoom's available. The one lens one year idea seems most attractive to those, like me, who perforce had to begin with the 'standard' 50mm, progressed (hem) onto zooms and then came back to the idea of stretching his technique by limiting the options.

And why O why (as we old farts are wont to say), do Pentax think the reduced sensor equivalent of that old 50mm is the right one to pitch at beginners? It was always an arbitrary, slightly too long length for general photography. Why not a 28mm f2.8 that offers a 42mm FOV? Should be a doddle to produce cheaply, especially in glorious plastic. Then, perhaps, a 24/28mm f2 Limited for those who appreciate the 'forever' aspect of it.

"The fixation with shallow depth of field is a recent phenomenon, provoked by tiny digicam sensors and their corresponding very short lenses. This would not be the right lens to get if you want that effect. There are other, better lenses for that.
Mike"

Pentax needs DA 24 - but I don't (or at least I don't know about it until a press release or TOP tells me I need it).

The thing is, I have a K28/2.8 on my K200D almost every time I go out of my home. The focal lenght on APS sensor is wonderful - a little bit wider than classic standard, but not quite wide angle (I think you wrote about that in one of old Sunday Photographers). Manual focusing forces thinking ahead and reduces shutter delay. Manual shutter and aperture eliminates exposure uncertainty (the stop-down metering is there, somewhere, but I consider it sort of witchcraft by now - along with light meters in general). The whole thing won't fit into a pocket, but it's convenient enough for me to carry pretty much everywhere. I can't see how one could get a better street photography tool.

"ADDENDUM: Several commenters have noted a website that has published the block diagrams of the new lens and the old FA lens and that claims they're identical. Here's the post. The two lenses are certainly related, but they're not identical."

"Still, I'd rather shoot ISO 400 at f2 than ISO 1600 at F4. Using the Canon 5D Mark I, which is supposed to have reasonable low light performance, I've found the high ISO pictures to be lacking. I do value a fast lens that lets me keep the ISO low."

Oh, for crying out loud. That is not the question here.

(1) We are talking about an f/2.4 lens, not an f/4 lens.

(2) Unlike the 5DII or any other body from Canon or Nikon, that little Pentax prime fits on bodies that give you real, usable 3-stop image stabilization.

Given that this setup is probably less than half the volume, half the weight, and less than 1/3 the price of a comparable D700 or 5DII with a normal prime, but has low light capabilities that approach those cameras, I really can't believe the amount of whining. It reminds me of this.

I have the Pentax FA* 24mm F2 lens and use it with K20D and on full-frame film bodies such as ME Super and ZX-L. The trouble is that it is rather heavy and soft wide-open, except for the center. It is certainly not a travel lens. So, you can't have it both ways.

"What do you think about the fact that the hybrid aspheric lens is made of plastic? Is plastic in every way today as good as fine glas?"

cola,
That's not a cause for concern. I'm not sure the word "plastic" is quite right and I'm not sure "made of" is accurate either...hybrid aspherics consist of a very thin layer of high-quality optical resin bonded to a spherical glass element. The method is widely used and I'm sure examples run the gamut of quality from very good to "oops." There is no easy way to make aspheric elements...all three methods have their advantages and disadvantages. Suffice to say that no inexpensive lens is likely to make use of either of the other two methods of manufacture.

Interestingly, the K-x and new K-r have 96%-frame viewfinders, so with the DA 21mm, it's exactly like a 100% finder, if you automatically trim just a hundred pixels off each edge of the resulting files.

Mike, problem with your counter-argument, is that Nikon has a 35/1.8 that's cheaper at MSRP by $20, and isn't that much bigger. I still think it's a sacrifice that doesn't yield enough payback. Nikon also currently has some really good DSLRs to go with that lens, so it's not like Pentax has an advantage in light sensitivity over them.

Nikon also currently has some really good DSLRs to go with that lens, so it's not like Pentax has an advantage in light sensitivity over them."

The Pentax K-x's light sensitivity is equal to or better than any Nikon APS-C camera. It should be. They use the same Sony sensors and, the Pentax implementation of these sensors is equal to or better than Nikon's.

And the Pentax bodies give you IS (worth a minimum of two, and more likely three stops) for all short primes. The Nikon bodies do not.

What remains to be seen is the relative performance of the Nikon and Pentax lenses at 2.4 and 2.8.

Mike, with all due respect, especially to the reaction of your previous post on this issue, I think you were right the first time. A good lens is a good lens, period. I, personally, have a feeling that this was a rather half-cooked effort by Pentax. The rumor has it that this new lens is full frame. It will be interesting to wait and see if it really is.

The only true 'innovation' here is the fact that it seems to be the very first prime lens by Pentax featuring the multitude of colors of the lens barrel.

The block diagrams might be the same, but the Olympus OM 50/1.8 generally has bad coating and most samples show decentering, while the Leica Summicron-M 50/2s coating is very good and mechanical construction is excellent.